The present invention relates generally to mass data storage and retrieval, and more particularly to apparatus and methods for authoring a digital versatile disk.
New mass data storage means provide not only for storing greater amounts of multimedia and other information, but also for more interactive data retrieval by consumers. For example, one such storage means is espoused by the xe2x80x9cDVD Specification for Read-Only Disc, Physical, File Format and Video Specificationsxe2x80x9d (DVD Consortium 1997), hereinafter referred to as the xe2x80x9cDVD Specificationxe2x80x9d. Other examples include further DVD-related technologies (e.g. DVD-Audio, DVD-RAM, etc.) as well as non-DVD technologies.
The Physical and File System portions of the DVD Specification defines the physical encoding and organization of data for storage on read-only digital versatile disk (xe2x80x9cDVD ROMxe2x80x9d) media. The Video portion of the DVD Specification defines a data set (xe2x80x9cDVD-Video data setxe2x80x9d) with which pre-recorded DVD-Video discs must conform in order to assure proper reading, decoding and playback when inserted into a media reader/decoder (xe2x80x9cDVD-playerxe2x80x9d). More specifically, the Video portion specifies how xe2x80x9ccontrol dataxe2x80x9d and audio/video xe2x80x9cpresentation dataxe2x80x9d are encoded and ordered within the data set. The control data determines how presentation of audio/video data will proceed when the disc is played back on a DVD-player and consists of low-level state information, data structures and instruction sets which govern what kinds of functions and user operations a DVD player can perform.
The DVD Specification is further hereby fully incorporated herein by reference as if repeated verbatim immediately hereinafter.
The process of encoding and authoring a DVD movie title, as currently practiced, includes a number of separate and distinct steps requiring similarly separate and distinct expertise. After movie production, raw film and/or video footage is edited, the soundtrack is edited and mixed, and a movie film or video master is created. This master is subsequently digitized, encoded as video and audio streams and stored as data files. In accordance with the DVD Specification, the Moving Pictures Expert Group (xe2x80x9cMPEG-1 or MPEG-2xe2x80x9d) format is used to encode the video streams and any one or more of a number of specified formats (e.g. MPEG-1or MPEG-2 Audio, Dolby AC-3, PCM) is used to encode the audio streams. Graphic data (i.e. still or moving images for creating menus and other presentation data) is also created and stored in conventional graphic files. Finally, authoring guidelines, the encoded audio and video stream files and the graphic files are gathered for the authoring phase.
During authoring, a DVD author utilizes the guidelines and file information to construct a DVD movie-title. The authored movie-title determines what a user of a resultant movie title will see and hear, and what kinds of interactions the user can command when the movie title is played back by a DVD-player. The author organizes the video, audio and (often author-created) subtitle files, divides the movie into segments (xe2x80x9cchaptersxe2x80x9d), creates menus, and specifies low-level instructions. The low-level instructions will set parameters, define fixed or optional jump points and their destinations and determine the order and options by which playback of still pictures, movie chapters and associated audio tracks will proceed based on the user""s menu selections and/or use of other DVD-player controls (i.e. typically using a remote control device).
Once authored, the author""s organizational decisions, subtitle, chapter and menu decisions, and low-level instructions are compiled into control data, and the encoded video, audio and subtitle streams, as well as the graphic data files, are multiplexed into presentation data, which together constitute the DVD-Video data set. Finally, this DVD-Video data is converted into a xe2x80x9cdisc image layoutxe2x80x9d file, which can be used to bum a xe2x80x9crite-once DVD-Rxe2x80x9d disc, or can be stored onto a tape to send to a DVD-ROM manufacturing plant for creating a xe2x80x9cmasterxe2x80x9d disc, which can then be used for replication.
Conventional DVD authoring systems comprise a computer system running an application-specific DVD authoring program. An exemplary, widely used conventional DVD authoring system is Scenarist-II.
Scenarist-II is essentially an attempted, nearly direct embodiment of the DVD Specification. Using Scenarist-II, an author organizes data streams, and constructs menus and DVD structures according to the DVD Specification. Top level structures (i.e. up to 99 xe2x80x9cVTSsxe2x80x9d and xe2x80x9cVTSMsxe2x80x9d, a xe2x80x9cVMGxe2x80x9d and a xe2x80x9cVMGMxe2x80x9d) are constructed by selecting the structure type and then populating the structure with one or more low-level command segments (xe2x80x9cprogram chainsxe2x80x9d or xe2x80x9cPGCsxe2x80x9d) including movie or menu references. Throughout this process, the author also selects from among available data formats, as well as from among the numerous DVD options and requisite parameters, using a number of provided lists and other data and parameter representations. Stated alternatively, all structures and PGC parameters, capabilities and references must be fully specified by the author on an ongoing basis during authoring.
Unfortunately, the DVD Specification is very complex, as are the conventional programs that attempt to embody it. Available options are extensive, as are the numerous listings of options and parameters within programs such as Scenarist-II. The potential combinations of structures and PGCs are also extensive, and many such combinations will not ultimately result in functional DVD movie-titles.
To make matters more difficult, the PGCs (i.e. basic and frequent constructs of the DVD Specification and therefore of programs such as Scenarist-II) are counter-intuitive. Often, many PGCs (including both operative and so-called xe2x80x9cdummyxe2x80x9d PGCs) must be used in specific combinations to provide a DVD consumer with even the most basic control capabilities. Limitations imposed by the DVD Specification must also be considered throughout the process. Thus, errors in planning and/or programming might well remain undetected until after a substantial number of structures are formed. In addition, given the sheer number of structures, PGCs, commands, options and parameters involved, identifying, locating and correcting errors is difficult and time-consuming.
Consequently, while providing extensive low-level control and an expedient authoring-to-compilation correspondence, conventional authoring systems require an extensive expertise with regard to both the DVD Specification and the authoring system itself. Further, even assuming such expertise, authoring is extremely time-consuming and is therefore typically very costly. In addition, even assuming resolution of other factors, the time and expertise required would likely prevent authoring of even a preliminary movie-title as a directorial aid during the movie production process.
A further disadvantage of conventional authoring systems is that experimentation and all but necessary modification are often compromised due to time and cost considerations. Thus, many DVD movie titles (due to limited budget to support expensive authoring time) provide a DVD consumer with only minimal playback control, navigation flexibility and interactivity.
Accordingly, there is a need for an authoring system and method that enables DVD authoring in a manner removed from the structures and low-level instruction sets of the DVD Specification, thereby reducing the time, cost and complexity of the authoring process.
There is further a need for such an apparatus and method whereby authoring can be conducted in an intuitive manner, while maximizing flexibility and access to features provided by or otherwise not in conflict with the DVD Specification.
The present invention provides a data processing-system based authoring system and method that essentially removes an author from consideration of the structures and low-level instruction sets of the DVD Specification. More specifically, the present authoring system removes the ordered tasks associated with creating DVD structures and programming PGCs, and replaces them instead with an interactive, intuitive and graphical authoring environment.
The present invention further provides for flexible program flow in response to control events. Many interactive controls, menu button destinations and other features that are possible in accordance with the DVD Specification can be specified by an author in multiple instances and according to quick, intuitive and interactively modifiable selections. Thus the invention facilitates authoring of a DVD movie title by even an inexperienced author with context sensitive responsiveness to DVD consumer instructions and other DVD player-generated events.
Accordingly, a preferred embodiment of the present invention comprises an authoring engine having an integrated interface with which an author performs the above tasks a data management engine for storing and recalling authoring information, a simulator for viewing progressive and/or comparatively authored movie titles prior to compiling, a compiler, a multiplexer and an emulator for viewing authored movie titles after compiling and multiplexing.
Included within and facilitating the ability of these elements to remove an author from the DVD Specification are several abstractions. Preferably, the interface provides such xe2x80x9cuser abstractionsxe2x80x9d as arranging movies (i.e. data streams including video, audio, subtitles, chapter points and other elements), creating menu layouts (i.e. menus, menu buttons and still or moving images with or without sound) and specifying connections among these arrangements and layouts, each in a simple and intuitive, yet highly flexible way. Further abstractions include a network or connection-switching abstraction and a number of control and router PGC abstractions from which the connection-switching abstraction is constructed.
Authoring instructions entered through the interface are preferably broken down into component parts and stored by the data management engine. The invoked compiler, using only summary authoring information, preferably constructs a skeleton form PGC layout structure comprised of PGC abstractions corresponding to the number of authored movie elements. The compiler then completes the layout structure according to author-selected and default source-target connections.
Further according to a preferred embodiment, during playback of a resultant DVD movie title, a source PGC abstraction is invoked in response to DVD player and/or consumer instructions. The source PGC abstraction determines target information and transfers control, through necessary router PGC abstractions, to a target PGC abstraction. The target, in accordance with the target information, plays a movie chapter, displays a menu, or sets and/or modifies one or more DVD parameter.
These and other objects, advantages and benefits of the present invention will become apparent from the drawings and specification that follow.